1. Field of the Invention
The present invention relates to an input device of a mobile terminal, and more particularly, to a mobile terminal embodying function keys positioned at a side surface of the mobile terminal using a piezoelectric sensor.
2. Description of the Related Art
In general, as various functions are added to a mobile terminal, operation of the mobile terminal becomes increasingly complex. Nowadays, mobile terminals provide various functions such as message transmission and reception, wireless Internet, phonebook management, schedule management, photographing, audiovisual communication, recording, and MP3 playing in addition to a communication function. Such a mobile terminal has function keys or hotkeys for rapidly executing specific functions of the above-described functions. For example, the mobile terminal may have a volume key, a camera key, and an MP3 key in a side surface.
Nowadays, a mobile terminal having a simple design is preferred. However, function keys or hotkeys provided in a side surface of a conventional mobile terminal are formed in a button type in which a key protrudes to the outside, and thus disturbing the simple design of the mobile terminal. Further, the conventional mobile terminal determines locations of the function keys or hotkeys in consideration of user convenience. However, in a conventional mobile terminal, convenient locations of the function keys or hotkeys are generally determined in consideration of a user holding the mobile terminal with the right hand and operating the keys with the right hand (typically, a right handed user), and thus the conventional mobile terminal is inconvenient to a user holding the mobile terminal in the left hand and operating with the left hand (typically, a left handed user).